It’s somewhat unusual for an architectural firm to have its offices right next to the construction site it’s partly responsible for.

Architect Dionys Ottl looks down from his workspace on the eighth floor of the high-rise on Hardenbergplatz in Berlin at one of his latest architecture projects as part of firm Hild und K: the concept shopping mall, Bikini Berlin, that rises around 100 meters from the ground. The so-called Bikinihaus, an elongated building from the 1950s that seems both modern and nostalgic after its revitalization at the same time, where individual visitors stroll on the newly created rooftop terrace and watch the goings-on in the adjacent zoo. Alongside the mall stands the sober administration building—now redeveloped, it houses the 25hours Hotel nestled in the back of the thick, green forest of the Tiergarten and half of Berlin. “Our precondition for taking on the project was that we were given a workspace on location,” recalls Dionys Ottl. “That was one of our main points. As an architect, you’re not alone on your paper or on your computer. As an architect, you need to create a discourse. There are hundreds of people involved in a project like this.”

With the Zoopalast on the left, the Bikini complex in the centre and the memorial church on the right, three iconic Berlin sites are gathered in one place.

Until October 2012 Hild und K’s studio was solely based in Munich. Then they were given the contract for the redevelopment of the Bikini Berlin.The post-war buildings from 1957, designed and built by architects Paul Schwebes and Hans Schorzberger, were once a meeting point and manufacturing facility for fashion that later fell into obscurity and were to be transformed into an urban centre. Centerpiece: the first concept shopping mall in Germany with curated retail concepts in the areas of fashion, food and design. Ottl and his colleagues knew the contractors, the Bayerische Hausbau from Munich, from previous collaborative housing projects in the Bavarian capital. “We apparently got noticed through our success in dealing with certain ideas that the contractor had and our frank discussions in a critical situation,” Ottl suspects. They first set themselves to work with a group of five individuals and four months later over twenty people were at the office in Berlin. The master plan by SAQ architects was already complete. Ottl and his colleagues had to sift through over 30,000 blueprints: “We thought to ourselves that this is the conversion of a building that has yet to be built. Apparently, that worked well.”

“As an architect, you’re not alone on your paper or on your computer. As an architect, you need to create a discourse.”

Since 1999 Dionys Ottl is leading the architecture firm Hild und K together with Andreas Hild, which came out of Hild und Kaltwasser Architekten. In 2011 Matthias Haber joined as a third partner. Although their reputation as renovation experts precedes them, the studio is just so much more. “Sometimes we have more renovation projects and at other times more construction. Right now, for example. It comes in intervals,” explains Ottl. Nevertheless, their renovation projects tend to stand out as they approach such projects in a more open, case by case, fashion. “Architectural firms often specialize in theoretical or manifesto-like aspects and have certain working theories. That’s not the case with us,” says Ottl. On the contrary, they were often told by contractors that they didn’t even know what to expect from them. Sometimes Dionys and his colleagues weren’t given contracts for this reason and sometimes precisely because of it: “Often we don’t even know what the result will be exactly when we start a project because we prefer to develop it through a discourse.” Communication, exploring boundaries, creating things without a precast mold—that’s what makes Hild und K different.

The different stages of redesigning Bikini Berlin

Dionys Ottl is still familiar with what the Bikini building was through the 1970s from some of his previous visits: A difficult location at the Zoo train station. And yet it was intended to be just the opposite. The building is born of the early reconstruction efforts from the time when Berlin was divided. After the Second World War, the goal was to establish a second nucleus in the city, analogous to the Mitte district—a ‘Center at the Zoo’. Dionys Ottl explains: “Around the turn of the century, that was already the plan. That’s why we have the Memorial Church. They wanted to create an entertainment district but after the war that was all over.” There’s always been competition between West and East Berlin, he says: “East Berlin was ahead for a long time thanks to the Frankfurter Tor. In the midst of the Cold War and with American support, the West then tried to catch up. From Ernst-Reuter-Platz all the way to the Urania.”

“Often we don’t even know what the result will be when we start a project because we prefer to develop it through a discourse.”

The name Bikini Berlin now refers to the entire ensemble of the Zoo Palast, the long building Bikinihaus, the office high-rise, the 25hours Hotel, and finally the parking garage. The Bikinihaus building that now houses the mall is its namesake. The name came about because the building is interrupted by an open floor in the middle, a kind of midriff section. “The city planning of the post-war period was meant to differentiate itself from the events of the Third Reich. That’s why they invented these buildings on stilts: Raised buildings under which the landscape and traffic can pass and for which the function is closer to the light and the sun,” Dionys Ottl explains. The Bikinihaus is one of the buildings that has its roots in this concept. Dionys Ottl adds: “That was also the time in which the bikini became a trend and since they manufactured women’s outerwear in the building, the Berlin taxi drivers soon started referring to it as such.”

“You would never come up with the idea of cutting four pillars out of the Brandenburg Gate to put a retail shop in it.”

The Bikini building remained neglected for a long time. “That has a lot to do with how city planning in West Berlin was generally done,” Ottl explains. For a long time, West Berlin was not a growing city and due to its isolated location suffered from the outward migration of its inhabitants. The concept of an industrial building in the middle of the city wasn’t met with great success either as more and more textile manufacturers moved their operations to developing countries with lower wages. There was no use for the Bikinihaus’ original purpose anymore. “Then lots of different things settled here but mostly import-export companies of some kind,” tells Ottl. “There were a couple of half-hearted renovation efforts in the 70s and 80s but nothing more significant than a few individual activities.” Moreover, a newly built road tunnel directed traffic past the Bikini building so that it was completely cut off from the Europa-Center and the neighboring pedestrian zone.

After reunification, everyone eventually dashed off to Mitte and Potsdamer Platz as a center of development. The West of Berlin stood in their shadow. Things really only got moving here around ten years ago. High-rises emerged and others sprouted alongside them. Today, the tunnel no longer exists. The revitalization of the Bikini Berlin is part of the overall concept for getting West Berlin back on its feet and making it more appealing again.

By shredding what was once the old facade of the Bikini building, Hild and K have found a singular material for Bikini's new facade.

Integrating a concept mall into a building from the 1950s is somewhat unusual. Normally, malls only function as prestige buildings nowadays. That’s why Dionys Ottl and his colleagues looked into what they could get out of the Bikini building without turning the whole thing upside down. “You would never come up with the idea of cutting four pillars out of the Brandenburg Gate to put a retail shop in it,” Ottl clarifies. The floating upper section of the Bikini building in its outer form was to be largely reconstructed but the interior was set to be converted and an open penthouse-like level to be added. Overall, the goal was not only to use somewhat incomplete, raw optics to highlight the temporary character of the shop but also that of the transformation in general.

Hild und K found the perfect solution for the pop-up concept with the wooden boxes. Anyone can arrange them however they like: “Things continue to change there even after two years. They can be rearranged. The concept is flexible and adaptable and allows for a great deal of freedom,” Ottl adds. The wooden frame structures with bars are like the exposed concrete on the ceiling, the cross-cut wooden parquet, the oak handrails and the matt green metal structures—which is the same green that covers bridges and streetlights all over the city—all left bare.

The architectural firm Hild und K was also involved in the interior of the building. “We continued the shell construction optics over all of the sections and influenced the entire physical appearance of the hall of the mall,” Ottl explains. As a transition to the public space, you can find the typical concrete sidewalk slabs for Berlin embedded in the floors. But Dionys is particularly pleased that the panorama window facing out over the zoo has been so well-received. He quips that it’s not often the case that something is actually used the way it was intended.

A selection of work by Hild und K

At the cinema Zoo Palast, the architectural firm was in charge of the shell construction, the basement and the integration of technical elements. Studio Aisslinger took on the interior development for the 25hours Hotel. They left the design with a more provisional feel and the reception desk is placed in the middle of load-bearing concrete shell structure with an otherwise raw aesthetic.

Ottl likes to work with pre-existing structures because it provides him with a jumping-off point. “With pre-existing structures, you have boundaries that you can explore or even occasionally cross,” he says. That applies, for example, for the interaction between old and new. “There are schools of thought that contend that old and new elements should remain completely separated when doing renovations. But we like to blur it all together because we want to make use of the full spectrum of architecture and move our work in more than just one direction. That was the case for Bikini Berlin. The façade panels are the best example. Hild und K had the old glass panels collected and shredded. Now their glass shards glisten in the plaster of the new façade components.

Although the Bikini Berlin project is now finished and there’s no prospect of a new specific contract yet, Hild und K are holding on to their second office location. “We’ve got a good team here and they’ve all proven themselves. There’s a good working atmosphere here that’s so rare. It would be a shame to give that up,” says Dionys Ottl, as a new group of people gets comfortable on the rooftop terrace below.

The ruins of the Kaiser Wilhelm Memorial Church have been preserved to this date and together with the 1950s annex designed by Egon Eiermann it counts as one of the main attractions in the West of Berlin.

Thank you, Dionys. From now on, we’ll see West Berlin with different eyes. You can find more information about the architectural firm Hild und K on their website. Info about Bikini Berlin is available on the mall’s website.